Electrolytic manganese dioxide has been used as a cathode active material for primary cells particularly alkali-manganese dry cells. Heretofore, dry cells suitable for an application for which a high discharge current (high rate discharge) is required, so-called dry cells excellent in the high rate discharge characteristic have been desired. Accordingly, as electrolytic manganese dioxide to be used as a cathode active material for alkali-manganese dry cells, electrolytic manganese dioxide excellent in the high rate discharge characteristic has been studied (for example, Patent Document 1).
However, along with electric power saving of a portable electronic device in recent years, dry cells which require a discharge current lower than the high rate discharge, so-called dry cells excellent in the middle rate discharge characteristic have been required. Thus, electrolytic manganese dioxide excellent in the middle rate discharge characteristic has been required.
As electrolytic manganese dioxide excellent in the middle rate discharge characteristic, the present inventors have reported electrolytic manganese dioxide having controlled potential and crystallinity (for example, Patent Document 2).